In automotive vehicles and the like, it has been more recently recommended that the fuel systems be sealed. However for safety reasons, it is desirable to provide a vapor collecting canister which should be periodically vented to the intake manifold as a function of ambient temperature. For example, one manufacturer recommends that the valve be closed at temperatures less than 100.degree. F. and open at temperatures above 130.degree. F.
The present invention is directed to a fuel vapor vent valve which will function to vent the fuel line in accordance with such requirements; which is relatively simple to manufacture; which can be preassembled for testing before final placement in sealed condition; and which utilizes parts that can be manufactured at relatively low cost and be readily handled.
In accordance with the invention, the fuel vapor vent valve comprises a plastic body including a base wall and a peripheral wall and a plastic cap including a base wall and a peripheral wall surrounding the peripheral wall of the plastic body. The peripheral wall of the base has a radially outwardly extending annular rib and the peripheral wall of the cap has a radially outwardly extending rib which are adapted to pass over one another to provide a snap fit during assembly. The base wall of said body having integral O-ring retaining means for retaining an O-ring. A bi-metallic disc is positioned in the body within the confines of the peripheral wall of the body and normally engages the O-ring. Integral stop means on said cap are adapted to be engaged by the bi-metal disc when the disc is caused to move to a position out of engagement with the O-ring upon increase of the ambient temperature.